MULTI-TIER KEYPAD ASSEMBLY
A multi-tier keypad includes at least a first circuit board having a first circuit and a second circuit board having a second circuit, wherein the second circuit board is disposed adjacent to the first circuit board, one or more first key assemblies for providing input to the first circuit when a first key assembly is pressed and one or more second key assemblies for providing input to the second circuit when a second key assembly is pressed. Apertures are formed though the first circuit board. These apertures allow the second key assemblies to extend through the first circuit board for providing input to the second circuit.
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The present invention relates generally to keypads for electronic devices, particularly hand-held electronic devices such as mobile telephones, palmtop computers, personal digital assistants (PDA's), or the like, and more specifically, to a multi-tier keypad assembly for such electronic devices.
Electronic devices, particularly hand-held electronic devices such as mobile telephones, palmtop computers, personal digital assistants (PDA's), and the like, comprise a class of devices typically requiring an operator to input information via a keypad, such as a numeric keypad, a small alphanumeric keypad, or the like. The keypad may be used for entering alphanumeric text and common commands, selecting menus to be displayed by a display, or the like. The keypad generally includes a set of keys contacting domes disposed over a circuit board. As the keys are pressed, they deform or compress the domes, providing input to the circuit board and tactile feedback to the operator of the electronic device. The amount of tactile feedback provided by the keys is described by the bounce performance of the keypad.
The trend toward miniaturization of electronic devices creates the need for smaller keypads. Further, the increasing complexity of operations required by such electronic devices creates the need for keypads having more keys, including keys having specialized characters and/or functionality. However, as more keys are packaged in smaller spaces, the keys become more concentrated or dense and the distances between the keys decrease, limiting the potential size of domes for providing tactile feedback when a key is pressed and reducing bounce performance. Moreover, a greater concentration of keys may hinder an operator from easily pressing a desired key, as the spaces between the keys become smaller than the width of a typical human fingertip.
Consequently, it would be desirable to provide a keypad having a high key density without loss of mechanical bounce performance. Further, it would be desirable to provide a keypad having multiple sets of keys which are differentiable from one another by adjusting the height of one or more of the sets of keys when keys of that set are to be used.
SUMMARY OF THE INVENTIONAccordingly, the present invention is directed to a multi-tier keypad capable of providing high key density without suffering a substantial loss of mechanical bounce performance. The keypad may also provide multiple sets of keys (e.g., numeric, alphabetic) which are differentiable from one another by adjusting the height of one or more of the sets of keys when keys of that set of keys are to be used for entering information.
In exemplary embodiments, the keypad includes a first circuit board having a first circuit and a second circuit board having a second circuit, wherein the second circuit board is disposed adjacent to the first circuit board (e.g., beneath the first circuit board), one or more first key assemblies for providing input to the first circuit when a first key assembly is pressed and one or more second key assemblies for providing input to the second circuit when a second key assembly is pressed. One or more apertures are formed though the first circuit board. These apertures allow the second key assemblies to extend through the first circuit board for providing input to the second circuit.
The keypad may further include two or more domes disposed over the first and second circuit boards, which are compressed by the first and second key assemblies for providing input to the first and second circuits, respectively. The first and second key assemblies may each comprise a key and a stalk coupled to the key which engage the domes for compressing the domes when the keys are pressed. Preferably, the stalks of the second key assemblies extend through the apertures formed in the first circuit board. In this manner, the size of the domes may be maximized, providing high key density without suffering a substantial loss of mechanical bounce performance.
In specific embodiments, the second circuit board may be movable between a first position relative to the first circuit board for positioning the keys of the second key assemblies at a first height relative to the keys of the first key assemblies and a second position relative to the first circuit board for positioning the keys of the second key assemblies at a second height relative to the keys of the first key assemblies. In this manner, the keypad may provide multiple sets of keys which are differentiable from one another by key height.
The multi-tier keypad may be utilized for providing input to an electronic device such as a mobile telephone, a palmtop computer, a personal digital assistant (PDA), or the like. In specific embodiments, the electronic device may include an actuator assembly coupled to the second circuit board for moving the second circuit board between the first and second positions, thereby raising and lowering the keys of the second key assemblies with respect to the keys of the first key assemblies.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not necessarily restrictive of the invention claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the general description, serve to explain the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings.
The keypad 100 further includes a plurality of key domes 116 and 118 positioned on the first and second circuit boards 102 and 106 over portions of the first and second circuits 104 and 108. The key domes 116 and 118 are compressed by the first and second key assemblies 110 and 112 for providing input to the first and second circuits 104 and 108, respectively. Each of the first and second key assemblies 110 and 112 comprise a generally flattened key 120 and 122 and a stalk or post 124 and 126 coupled to and extending downward from the key 120 and 122 which engages a respective one of the domes 116 and 118 for compressing the dome 116 and 118 when the key is pressed. The stalks 126 of the second key assemblies 112 are elongated compared to the stalks 124 of the first key assemblies 110 and extend through the apertures 114 formed in the first circuit board 102. For example, when the keypad 100 is utilized for providing input to an electronic device such as a mobile telephone, or the like, a specific key 120 or 122 may be labeled with a letter or a number (e.g. the number “2”), and the number “2” key may be pressed by an operator in the course of inputting a telephone number to the mobile telephone via the keypad 100. By pressing the number “2” key 120 or 122, a circuit of the first circuit board 102 or the second circuit board 106 is completed when the stalk 124 or 126 of the key assembly 110 or 112 containing of the number “2” key 120 or 122 depresses or collapses the key dome 116 or 118 associated with that key assembly 110 or 112 contacting the circuit 104 or 108 on the circuit board 102 or 106 actuating the circuit (e.g., closing the circuit 104 or 108). Completion of the circuit 104 or 108 formed upon the circuit board 102 or 106 indicates that the key has been pressed.
In exemplary embodiments, each key dome 116 and 118 may be formed of a metal such as a spring steel; an elastomeric material such as a synthetic rubber or plastic, having a metal contact formed therein; or the like. When compressed, the key dome 116 and 118 closes the circuit 104 and 108 for registering a key press. However, those of skill in the art will appreciate that various equipage may be utilized for completing the circuit formed upon the first circuit board 102 or the second circuit board 106 without departing from the scope and intent of the present invention. For example, instead of key domes, an electrically conductive material may be coupled to the end of the stalk 124 or 126 for directly contacting the first circuit board 102 or the second circuit board 106. A spring may be used for returning the key assembly to a non-pressed position. Similarly, the circuit 104 and 108 may employ capacitive coupling, force sensing (e.g., via a force sensor), or like technologies for registering a key press when the dome is compressed. Such technologies are known in the art.
The first and second key assemblies 110 and 112 are formed as part of one or more key mats 128, 130 and 132. For example, in the embodiment shown in
In the embodiment shown in
The multi-tier arrangement of the first and second circuit boards 102 and 106 allows the individual key domes 116 and 118 to be made larger (e.g., to have a greater diameter, width, height, and/or surface area) than would be possible with conventional single-circuit board keypads having similar key densities. For example, as shown in
In the embodiment illustrated in
As in the embodiment illustrated in
By allowing the sets of keys 120 and 122 to be positioned at varying relative heights, increased access may be provided to one set of keys 120 or 122, while limiting inadvertent activation of the other set of keys 122 or 120. For example, in an electronic device such as a mobile telephone or the like, the set of first keys 120 may comprise a numeric keypad having keys for the numbers zero (“0”) through nine (“9”) and operands such as an asterisk (“*”) and an octothorpe (“#”), while the set of second keys 122 may comprise an alphabetic keypad having keys for the letters “A” through “Z” and various punctuation symbols (e.g., a period (“.”), a comma (“,”) or the like). When an operator of the device wishes to input numeric information (e.g., a telephone number), the set of second keys 122 may be positioned below the set of first keys 120. In this manner, the numeric keys of the set of first keys 120 are more easily accessed, while the alphabetic keys of the set of second keys 122 are recessed to prevent inadvertent actuation. Conversely, when the operator wishes to input alphabetical information (e.g., text for text messaging), the set of second keys 122 may be positioned above the set of first keys 120. Should the operator wish to enter alphanumeric information, the sets of first and second keys 120 and 122 may be placed at the same level. Those of ordinary skill in the art will appreciate that keys for other characters such as other punctuation marks, parenthetical marks, symbols, abbreviations, characters from other languages, and the like, may be included with the sets of first and/or second keys 120 and 122. Further, the use of keys having other functionalities, such as keys comprising a directional keypad, a menu button, or the like, would not depart from the scope of the present invention.
In exemplary embodiments, the keypad 100 of the present invention may be utilized for providing input to an electronic device such as the mobile telephone 150 shown in
As shown in
An actuator assembly 158 may coupled to the second circuit board 106 for raising and lowering the set of second keys 122 with respect to the set of first keys 120. For example, in exemplary embodiments, the actuator assembly 158 may be coupled to the second circuit board 106 for moving the second circuit board 106 and key mat 132 toward or away from the first circuit board 102, in the manner illustrated in
Those of skill in the art will appreciate that various other actuator mechanisms may be devised for shifting the second 122 and or first keys 120 without departing from the scope and intent of the present invention. Moreover, while the mobile telephone 150 illustrated in
The mobile telephone 150 may further include components for providing wireless communication of voice and/or data information with external sources such as a base station, a cellular communication system tower, another mobile communication device, or the like. For example, the mobile telephone 150 may comprise internal components including a processing system, memory, a transceiver assembly including a transmitter and receiver or transceiver, an antenna, a data card reader for receiving a data card (e.g., a subscriber identification module (SIM) card or a user identification module (UIM) card), a speaker or earpiece assembly, a microphone, a power source such as a battery, and the like. Additionally, it is contemplated that the mobile telephone 150 may provide functions other than telephony. For example, the mobile telephone 150 may provide functions common to hand held computers or personal digital assistants, portable gaming devices, or the like. In such embodiments, the mobile telephone may further include a suitable processing system, extended memory, a touch screen overlaying display for tactile input of data, or the like.
In
It is believed that the present invention and many of its attendant advantages will be understood by the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely an explanatory embodiment thereof, it is the intention of the following claims to encompass and include such changes.
Claims
1. A keypad, comprising:
- a first circuit board including a first circuit, the first circuit board laving an aperture formed there through;
- a first key assembly for providing input to the first circuit when the first key assembly is pressed;
- a second circuit board including a second circuit, the second circuit board disposed adjacent to the first circuit board;
- a second key assembly for providing input to the second circuit when the second key assembly is pressed; and
- a keymat including the first key assembly and the second key assembly.
- wherein the second key assembly extends through the aperture formed in the first circuit board for providing input to the second circuit.
2. The keypad as claimed in claim 1, further comprising:
- a first dome disposed over the first circuit board, the first dome for being compressed by the first key assembly for providing input to the first circuit; and
- a second dome disposed over the second circuit board, the second dome for being compressed by the second key assembly for providing input to the second circuit.
3. The keypad as claimed in claim 2, wherein the first key assembly comprises a first key and a first stalk coupled to the first key, the first stalk engaging the first dome for compressing the first dome when the first key is pressed, and the second key assembly comprises a second key and a second stalk coupled to the second key, the second stalk extending through the aperture formed in the first circuit board for compressing the second dome when the second key is pressed.
4. The keypad as claimed in claim 3, wherein at least one of the first key and the second key has a first diameter and a corresponding one of the first dome and the second dome has a second diameter, the second diameter being greater than the first diameter.
5. The keypad as claimed in claim 4, wherein the first key has a first footprint and the second key has a second footprint, and at least one of the first dome extends into the second footprint and the second dome extends into the first footprint.
6. The keypad as claimed in claim 3, wherein the second circuit board is movable between a first position relative to the first circuit board for positioning the second key at first height relative to the first key and a second position relative to the first circuit board for positioning the second key at a second height relative to the first key.
7. The keypad as claimed in claim 6, wherein the first key has a relative height and the first height is greater than the relative height of the first key and the second height is less than the relative height of the first key.
8. (canceled)
9. (canceled)
10. The keypad as claimed in claim 2, wherein the first and second domes comprise an electrically conductive material so that compression of the first dome completes the first circuit and compression of the second dome completes the second circuit.
11. A hand-held electronic device, comprising;
- a housing;
- a keypad disposed in the housing, the keypad including:
- a first circuit board including a first circuit, the first circuit board having an aperture formed there through;
- a first key assembly including a first key, the key assembly for providing input to the first circuit when the first key is pressed;
- a second circuit board disposed beneath to the first circuit board, the second circuit board including a second circuit; and
- a second key assembly including a second key, the second key assembly for providing input to the second circuit when the second key is pressed,
- wherein the second key assembly extends through the aperture formed in the first circuit board for providing input to the second circuit the second circuit board being movable between a first position relative to the first circuit board for positioning the second key at first height relative to the first key and a second position relative to the first circuit board for positioning the second key at a second height relative to the fist key.
12. The pad hand-held electronic device as claimed in claim 11, further comprising:
- a first dome disposed over the first circuit board, the first dome for being compressed by the first key assembly for providing input to the first circuit; and
- a second dome disposed over the second circuit board, the second dome for being compressed by the second key assembly for providing input to the second circuit.
13. The hand-held electronic device as claimed in claim 12, wherein the first key assembly comprises a first stalk coupled to the first key, the first stalk engaging the first dome for compressing the first dome when the first key is pressed, and the second key assembly comprises a second stalk coupled to the second key, the second stalk extending through the aperture formed in the first circuit board for compressing the second dome when the second key is pressed.
14. (canceled)
15. The hand-held electronic device as claimed in claim 13, wherein the first key has a relative height and the first height is greater than the relative height of the first key and the second height is less than the relative height of the first key.
16. The hand-held electronic device as claimed in claim 15, further comprising an actuator assembly coupled to the second circuit board for moving the second circuit board between the first and second positions.
17. A mobile telephone, comprising:
- a housing;
- a keypad disposed in the housing, the keypad including: a first circuit board including a first circuit, the first circuit board having an aperture formed there through; a first key assembly including a first key, the key assembly for providing input to the first circuit when the first key is pressed; a second circuit board disposed beneath to the first circuit board, the second circuit board including a second circuit; and a second key assembly including a second key, the second key assembly for providing input to the second circuit when the second key pressed, wherein the second key assembly extends through the aperture formed in the first circuit board for providing input to the second circuit the second circuit board being movable between a first position relative to the first circuit board for positioning the second key at first height relative to the first key and a second position relative to the first circuit board for positioning the second key at a second height relative to the first key.
18. The keypad as claimed in claim 17, further comprising:
- a first dome disposed over the first circuit board, the first dome for being compressed by the first key assembly for providing input to the first circuit; and
- a second dome disposed over the second circuit board, the second dome for being compressed by the second key assembly for providing input to the second circuit.
19. The keypad as claimed in claim. 18, wherein the first key assembly comprises a first stalk coupled to the first key, the first stalk engaging the first dome for compressing the first dome when the first key is pressed and the second key assembly comprises a second stalk coupled to the second key, the second stalk extending through the aperture formed in the first circuit board for compressing the second dome when the second key is pressed.
20. (canceled)
21. A keypad, comprising:
- a first circuit board including a first circuit, the first circuit board having an aperture formed there through;
- a first keymat including a first key assembly for providing input to the first circuit when the first key assembly is pressed;
- a second circuit board including a second circuit, the second circuit board disposed adjacent to the first circuit board; and
- a second keymat including a second key assembly for providing input to the second circuit when the second key assembly is pressed,
- wherein the second key assembly extends through the first keymat and the aperture formed in the first circuit board for providing input to the second circuit.
22. The keypad as claimed in claim 21, further comprising:
- a first dome disposed over the first circuit board, the first dome for being compressed by the first key assembly for providing input to the first circuit; and
- a second dome disposed over the second circuit board, the second dome for being compressed by the second key assembly for providing input to the second circuit.
23. The keypad as claimed in claim 22, wherein the first key assembly comprises a first key and a first stalk coupled to the first key, the first stalk engaging the first dome for compressing the first dome when the first key is pressed, and the second key assembly comprises a second key and a second stalk coupled to the second key, the second stalk extending through the aperture formed in the first circuit board for compressing the second dome when the second key is pressed.
24. The keypad as claimed in claim 23, wherein at least one of the first key and the second key has a first diameter and a corresponding one of the first dome and the second dome has a second diameter, the second diameter being greater than the first diameter.
25. The keypad as claimed in claim 24, wherein the first key has a first footprint and the second key has a second footprint, and at least one of the first dome extends into the second footprint and the second dome extends into the first footprint.
26. The keypad as claimed in claim 23, wherein the second circuit board is movable between a first position relative to the first circuit board for positioning the second key at first height relative to the first key and a second position relative to the first circuit board for positioning the second key at a second height relative to the first key.
27. The keypad as claimed in claim 26, wherein the first key has a relative height and the first height is greater than the relative height of the first key and the second height is less than the relative height of the first key.
Type: Application
Filed: Dec 17, 2004
Publication Date: Jun 22, 2006
Applicant:
Inventor: Lovleen Chadha (San Diego, CA)
Application Number: 11/015,086
International Classification: H01H 1/10 (20060101);